<?php
/**
 * show-processor.php
 *
 * This file implements the processor for the SHOW statements.
 *
 * Copyright (c) 2010-2012, Justin Swanhart
 * with contributions by André Rothe <arothe@phosco.info, phosco@gmx.de>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */
if (!defined('HAVE_SHOW_PROCESSOR')) {

    require_once(dirname(__FILE__) . '/../constants.php');
    require_once(dirname(__FILE__) . '/../expression-types.php');
    require_once(dirname(__FILE__) . '/limit-processor.php');
    require_once(dirname(__FILE__) . '/abstract-processor.php');

    /**
     * 
     * This class processes the SHOW statements.
     * 
     * @author arothe
     * 
     */
    class ShowProcessor extends AbstractProcessor {

        private $limitProcessor;

        public function __construct() {
            $this->limitProcessor = new LimitProcessor();
        }

        public function process($tokens) {
            $resultList = array();
            $category = "";
            $prev = "";

            foreach ($tokens as $k => $token) {
                $upper = strtoupper(trim($token));

                if ($this->isWhitespaceToken($token)) {
                    continue;
                }

                switch ($upper) {

                case 'FROM':
                    $resultList[] = array('expr_type' => ExpressionType::RESERVED, 'base_expr' => trim($token));
                    if ($prev === 'INDEX' || $prev === 'COLUMNS') {
                        continue;
                    }
                    $category = $upper;
                    break;

                case 'CREATE':
                case 'DATABASE':
                case 'FUNCTION':
                case 'PROCEDURE':
                case 'ENGINE':
                case 'TABLE':
                case 'FOR':
                case 'LIKE':
                case 'INDEX':
                case 'COLUMNS':
                case 'PLUGIN':
                case 'PRIVILEGES':
                case 'PROCESSLIST':
                case 'LOGS':
                case 'STATUS':
                case 'GLOBAL':
                case 'SESSION':
                case 'FULL':
                case 'GRANTS':
                case 'INNODB':
                case 'STORAGE':
                case 'ENGINES':
                case 'OPEN':
                case 'BDB':
                case 'TRIGGERS':
                case 'VARIABLES':
                case 'DATABASES':
                case 'ERRORS':
                case 'TABLES':
                case 'WARNINGS':
                case 'CHARACTER':
                case 'SET':
                case 'COLLATION':
                    $resultList[] = array('expr_type' => ExpressionType::RESERVED, 'base_expr' => trim($token));
                    $category = $upper;
                    break;

                default:
                    switch ($prev) {
                    case 'LIKE':
                        $resultList[] = array('expr_type' => ExpressionType::CONSTANT, 'base_expr' => $token);
                        break;
                    case 'LIMIT':
                        $limit = array_pop($resultList);
                        $limit['sub_tree'] = $this->limitProcessor->process(array_slice($tokens, $k));
                        $resultList[] = $limit;
                        break;
                    case 'FROM':
                    case 'DATABASE':
                        $resultList[] = array('expr_type' => ExpressionType::DATABASE, 'name' => $token,
                                              'no_quotes' => $this->revokeQuotation($token), 'base_expr' => $token);
                        break;
                    case 'FOR':
                        $resultList[] = array('expr_type' => ExpressionType::USER, 'name' => $token,
                                              'no_quotes' => $this->revokeQuotation($token), 'base_expr' => $token);
                        break;
                    case 'INDEX':
                    case 'COLUMNS':
                    case 'TABLE':
                        $resultList[] = array('expr_type' => ExpressionType::TABLE, 'table' => $token,
                                              'no_quotes' => $this->revokeQuotation($token), 'base_expr' => $token);
                        $category = "TABLENAME";
                        break;
                    case 'FUNCTION':
                        if (PHPSQLParserConstants::isAggregateFunction($upper)) {
                            $expr_type = ExpressionType::AGGREGATE_FUNCTION;
                        } else {
                            $expr_type = ExpressionType::SIMPLE_FUNCTION;
                        }
                        $resultList[] = array('expr_type' => expr_type, 'name' => $token,
                                              'no_quotes' => $this->revokeQuotation($token), 'base_expr' => $token);
                        break;
                    case 'PROCEDURE':
                        $resultList[] = array('expr_type' => ExpressionType::PROCEDURE, 'name' => $token,
                                              'no_quotes' => $this->revokeQuotation($token), 'base_expr' => $token);
                        break;
                    case 'ENGINE':
                        $resultList[] = array('expr_type' => ExpressionType::ENGINE, 'name' => $token,
                                              'no_quotes' => $this->revokeQuotation($token), 'base_expr' => $token);
                        break;
                    default:
                    // ignore
                        break;
                    }
                    break;
                }
                $prev = $category;
            }
            return $resultList;
        }
    }

    define('HAVE_SHOW_PROCESSOR', 1);
}
